The octopus can see with its skin

Octopuses are well known for changing the colour, patterning, and texture of their skin to blend into their surroundings and send signals to each other, an ability that makes them both the envy of, and inspiration for, army engineers trying to develop cloaking devices. As if that wasn’t already impressive enough, research published today in the Journal of Experimental Biology shows that octopus skin contains the pigment proteins found in eyes, making it responsive to light.

Reference: Ramirez, M. D. & Oakley, T. H. (2015). Eye-independent, light-activated chromatophore expansion (LACE) and expression of phototransduction genes in the skin of Octopus bimaculoides. J. Exp. Biol. doi: 10.1242/jeb.110908.

The common octopus (Octopus vulgaris). New research shows that octopus skin contains the light-sensitive opsin protein, suggesting that these clever cephalopods can “see” without using their eyes. Photograph: Dave King/Getty Images/Dorling Kindersley

3:28pm // My teacher’s critiques to my essay outline seemed highly subjective and were incredibly frustrating (or maybe I just need to learn how to accept criticism better). Anyways, off to work and then back home to study for a genetics exam!

Bacteria cooperate to repair damaged siblings

A University of Wyoming faculty member led a research team that discovered a certain type of soil bacteria can use their social behavior of outer membrane exchange (OME) to repair damaged cells and improve the fitness of the bacteria population as a whole.

Daniel Wall, a UW associate professor in the Department of Molecular Biology, and others were able to show that damaged sustained by the outer membrane (OM) of a myxobacteria cell population was repaired by a healthy population using the process of OME. The research revealed that these social organisms benefit from group behavior that endows favorable fitness consequences among kin cells.

Wall says, to the research group’s knowledge, this is the first evidence that a bacterium can use cell-content sharing to repair damaged siblings.

“It is analogous to how a wound in your body can be healed,” Wall says. “When your body is wounded, your cells can coordinate their functions to heal the damaged tissue.”

Wall was the senior and corresponding author on a paper, titled “Cell Rejuvenation and Social Behaviors Promoted by LPS Exchange in Myxobacteria” that was published in the May 18 online issue of the Proceedings of the National Academy of Sciences (PNAS).

(Image: Michiel Vos) - Antisocial Behavior in Cooperative Bacteria (or, Why Can’t Bacteria Just Get Along?). PLoS Biology Vol. 3/11/2005, e398 doi:10.1371/journal.pbio.0030398

Some 100,000 Myxococcus xanthus cells amassed into a fruiting body with spores.

Struggle in my classroom can’t be established until students trust me. Demonstrating caring, sharing my goals for them, explaining the course goals and recognizing and communicating feelings to my classes are a necessary part of teaching. Students have to know that you’re going to catch them before they’re willing to take a leap. They have to struggle to learn something meaningful, and learning to overcome struggle is the most valuable thing I can teach them. Their success comes down to understanding where they are on a daily basis.
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This week, The New York Times posted an awesome article about bird warning calls and a researcher who spends his days listening to them

When they notice a threat or a predator, birds like buntings or chickadees will chirp a special alarm. This call is passed on by other birds, spreading out ahead of the predator’s arrival so quickly that, miles away, the warning might arrive several minutes before the danger does. 

What’s even cooler is that birds aren’t the only ones listening to the alarm calls. Creatures from mice to monkeys have been known to scurry in response to a song, often adding alarm calls of their own. 

These alarm calls could be a form of proto-language, capable of cross-species transmission. And you thought your three semesters of French were impressive! We used to believe that things like language, tool use, and culture were strictly human endeavors, proof of some privileged position we had attained above other animals. Research like this continues to shatter those ideas, but don’t worry, it doesn’t make you less special. It simply broadens our connection with nature. 

Tom McFadden, the lyrical mastermind behind Science With Tom (you may remember him from such hits as this, this, or this) created a science rap about this research which I’ve posted up top. As if that wasn’t cool enough, the flow is accompanied by a beat made from actual bird alarm calls, crafted by beatboxer (birdboxer?) Ben Mirin.

You can listen to more of Ben’s awesome birdbeats here. Let me know if they inspire any of your own creations! Chirp chirp!

So why did they start eating bamboo? No meat around? Meat moved too fast to catch? They really like the taste?

Giant Pandas Meant to Eat Meat, Not Bamboo

Giant pandas are known for their voracious appetite for bamboo, but these furry mammals are actually meant to eat meat.

That’s at least according to a new study published in the journal mBio®, which details how the gut bacteria of giant pandas are not the type for efficiently digesting bamboo. Instead, they boast a carnivore-like gut microbiota predominated by bacteria such as Escherichia/Shigella and Streptococcus, a team of Chinese researchers says.

“Unlike other plant-eating animals that have successfully evolved, anatomically specialized digestive systems to efficiently deconstruct fibrous plant matter, the giant panda still retains a gastrointestinal tract typical of carnivores,” lead study author Zhihe Zhang, director of the Chengdu Research Base of Giant Panda Breeding, China, said in a press release. “The animals also do not have the genes for plant-digesting enzymes in their own genome. This combined scenario may have increased their risk for extinction.”

The octopus has a unique ability. It can change the color, pattern and even texture of its skin not only for purposes of camouflage but also as a means of communication. The most intelligent, most mobile and largest of all mollusks, these cephalopods use their almost humanlike eyes to send signals to pigmented organs in their skin called chromatophores, which expand and contract to alter their appearance.

A new study by UCSB scientists has found that the skin of the California two-spot octopus (Octopus bimaculoides) can sense light even without input from the central nervous system. The animal does so by using the same family of light-sensitive proteins called opsins found in its eyes—a process not previously described for cephalopods. The researchers’ findings appear in the Journal of Experimental Biology.

“Octopus skin doesn’t sense light in the same amount of detail as the animal does when it uses its eyes and brain,” said lead author Desmond Ramirez, a doctoral student in the Department of Ecology, Evolution and Marine Biology (EEMB). “But it can sense an increase or change in light. Its skin is not detecting contrast and edge but rather brightness.”

Continue Reading.

Octopus’s skin detects light the same way its eyes do

Octopuses have a well-known ability to change the color and texture of their skin in order to blend in with their environment or to communicate with other organisms. They are able to do this because of special pigmented organs in their skin, called chromatophores, which receive signals from the animal’s eyes and then expand and contract as needed to change the skin’s appearance. A new study shows that the octopus’s eyes are not the only way that the chromatophores receive these signals, however: octopus skin can change its appearance with no input from the eyes at all.

Researchers at UC Santa Barbara studied the California two-spot octopus (Octopus bimaculoides) and found that its skin changed color when exposed to white light as a result of the chromatophores in the skin contracting, even with no sensory input from the eyes. Further experiments showed that the chromatophores responded the quickest to blue light. This process, called light-activated chromatophore expansion, shows that the chromatophores and light sensors are linked within the skin and do not rely on input from the central nervous system. The skin could not sense light with the same detail as the eyes and brain, with its responses being limited to changes in brightness, but the changes were undeniably there.

Researchers dug deeper and found that sensory neurons in the octopus’s skin contained rhodopsin, a light-sensitive opsin protein found in the octopus’s eyes. This reveals a heretofore-unknown evolutionary adaptation in which cellular mechanisms for light detection in octopuses’ eyes have been adopted by their skin as well.

Other marine molluscs have light-sensing skin, but researchers are not sure if that is the result of opsins or other adaptations. If other molluscs’ skin also uses these proteins to change appearance, researchers hope to discover whether the similar adaptations evolved independently or from a common ancestor.

  • Based on materials originally provided by UC Santa Barbara
  • Journal reference: M. D. Ramirez, T. H. Oakley. Eye-independent, light-activated chromatophore expansion (LACE) and expression of phototransduction genes in the skin of Octopus bimaculoides. Journal of Experimental Biology, 2015; 218 (10): 1513 DOI:10.1242/jeb.110908
  • Image: A California two-spot octopus (Credit: Partial Pressure Production, via marinebio.org)
  • Submitted by volk-morya
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Sea Butterflies in Danger

Pteropods, affectionately nicknamed “sea butterflies,” are at the bottom of the ocean food chain.

If pteropod populations decline or disappear due to rising acidity, the consequences for marine life could be dire.

By: NOVA PBS.